Hey all, iv decided to buy a new b16a2 engine and resleve the block for my Turbosetup, becasue i can't just buy a block out here in Australia and + the b16 engine is **** cheep.... Anyway im ordering new pistons / rods off Ben.. and im about to pay for them. and have them shiped over here... i decided to go with 9:1 ratio, but iv been reading / understanding people go with wider pistons to increase the Litre size of the engine, ie boring it out. to 84mm instead of 81 (stock) also boring the engine out to 84mm that like makes it a 1760cc engine correct ?

im getting a local shop to do the cast iron sleves for me, for him to increase the bore size is very simple. Is there such a thing as a wider piston for the b16a2 engine for people with larget bores ?

Or am i understandin this wrong.. and people that bore there blocks just bore the blocks larger to 84mm and leave the pistons still at 81mm ?

grr me very confused

and i don't wanta get the wrong pistons off ben...

 

If you bore it to 84mm, you would need to get the piston the same size. But remember if you are going to bore the b16 you are gonna need to resleeve it...

art

 

ok.. thats that question sorta answered yeah i it will be over bored then the cast iron sleves go in i want the final size to be 84mm.
having a 84mm size engine sorta turns my b16 engine into a b17.6 engine yeah ? close to a b18 ? thus increasing power....
or should i jsut forget about the idea and keep to the stock sleve size. ?
i was just figuring this.. bc it won't cost me extra to make the size larger...tobegin with.

 

Why not just go .020 over(.5mm) for 84.5mm bore. You will have somewhere around 1.8L and a almost "perfect" rod to stroke ratio of 1.74:1. And this # was not from Endyn but other engine builders say the same thing. Even tho alot of people think larry came up with this ratio, its been know by engine builders for years. I think he just introduced it to the Honda world and took credit for it.

art

 

That sounds Perfect.. and exctualy what i was getting to...

So what size pistons would i order...am i right to assume .5mm would be then 82mm ? piston size ? bc stock b16 is 81.5 ? yeah ?
so ordering JE 9:1 at 82mm ? would be what i ask ben for ? yeah
?

B/w thanks heeps for ya help Art ya a turbo Legand !

Regards James

 

Well the stock bore on the b16 is 81mm, but if you want it closer to 1.8Liters then you would need to bore it out 3.5mm to aquire the 84.5mm. Im not sure if you are wanting 84.5, to get 1.8L, or 81.5 to to stay around 1.6L.

And Im not a turbo legend, Im just learing just like everyone else. There is sooooooo much to be learned.

art

 

is 81.5 the so called the "perfect rod to stroke ratio of 1.74:1"
or is that the 84.5mm the "perfect rod to stroke ratio of 1.74:1"

jsut still a little confused... if 81.5 mm is going to be more optimal.. ill do that.. just don't wanta get the wrong size pistons.

"yeha i know there is nothing perfect.. " ehhe

Im wanting to get close to 1.8L because from what i have read it tends to be much better performace wise and its like stayin with a b16.. but getting a b18.

Regards James

 

I'm pretty sure that the bore size does not affect r/s ratio. Correct me if I am wrong. A change in the rod length or the stroke would change the r/s ratio.

 

Correct sir!

Divide rod length by stroke to get R/S ratio.

There is also B/S or bore to stroke ratio....don't know what its function is though.

 

You need the piston bore to correct for your cylender bore. So if you're looking to (sleeve and bore to) go with a 84.5mm cylender bore (to increase displacement) tell Ben you want 84.5mm pistons.


[Modified by Bert, 10:15 PM 2/8/2002]

 

is 81.5 the so called the "perfect rod to stroke ratio of 1.74:1"
or is that the 84.5mm the "perfect rod to stroke ratio of 1.74:1"

jsut still a little confused... if 81.5 mm is going to be more optimal.. ill do that.. just don't wanta get the wrong size pistons.

"yeha i know there is nothing perfect.. " ehhe

Im wanting to get close to 1.8L because from what i have read it tends to be much better performace wise and its like stayin with a b16.. but getting a b18.

Regards James

 

As previous posters said, cylender bore has nothing to do with rod/stroke ratio, which is determined by the rods and the crank. Since you are only changing the size of the pistons, you r/s ratio will not change one bit.